Anopla (for changes in taxonomy, see reference from 2019) has long been used as name for a class of marine worms of the phylum Nemertea, characterized by the absence of stylets on the proboscis, the mouth being below or behind the brain, and by having separate openings for the mouth and proboscis. The other long used class of Nemertea are the Enopla (for changes in taxonomy, see reference from 2019). Although Anopla is a paraphyletic grouping, it is used in almost all Scientific classifications. Anopla is divided into two orders: Palaeonemertea and Heteronemertea.